Contemporary processors commonly employ caches to improve performance. Caching allows data and/or instructions to be pre-fetched and stored to memory accessible to execution units in fewer cycles than required to access main memory. Performance is thus improved by reducing the latency (delay) associated with retrieving required data or instructions. However, lower latency implies higher power consumption.
In some applications, however, power consumption by a processor is an important consideration. For instance, power consumption may be a significant concern for Customer Premises Equipment (CPE) for an Advanced Digital Subscriber Line (ADSL) communications link powered through a Universal Serial Bus (USB) connection, where the power available through the USB connection is constrained.
There is, therefore, a need in the art for improving the performance/power ratio of a processor by reducing power consumption without substantially degrading performance.